Here in UK, unless you are planning a sunshine holiday this winter (I wish!) put all the summer clothes in a bag or box clearly labelled and put it somewhere out of the way.
In our very variable climate layering clothes is almost essential so some summer items can be worn all year round under an extra layer.
You might take this opportunity to do some weeding out, or you could just put them all away and make those decisions next summer. It depends on how you're feeling, how much time you've got and maybe on how much extra storage space you've got.
But now you have more space in your wardrobe/cupboard/drawers.
Just two more sleeps till you have a wardrobe with only things you can wear!